The manifest file is the primary way to interact with bootstrap-vz.
Every configuration and customization of a Debian installation is specified in this file.

The manifest format is YAML or JSON. It is near impossible to run the
bootstrapper with an invalid configuration, since every part of the
framework supplies a json-schema that
specifies exactly which configuration settings are valid in different
situations.

Many of the settings in the example manifests use strings like
debian-{system.release}-{system.architecture}-{{"{%y"}}}{{"{%m"}}}{{"{%d"}}}.
These strings make use of manifest variables, which can cross reference
other settings in the manifest or specific values supplied by the
bootstrapper (e.g. all python date formatting variables are available).

Any reference uses dots to specify a path to the desired manifest
setting. Not all settings support this though, to see whether embedding
a manifest variable in a setting is possible, look for the
manifestvars label.

To insert a literal {foo} use double braces, that is {{foo}}.
For example in a shell command where you may want to use the
expression ${foo}, use ${{foo}} instead.

name: The name of the resulting image.
When bootstrapping cloud images, this would be the name visible in
the interface when booting up new instances.
When bootstrapping for VirtualBox or kvm, it’s the filename of the
image.
requiredmanifestvars

workspace: Path to where the bootstrapper should place images
and intermediate files. Any volumes will be mounted under that path.
required

tarball: debootstrap has the option to download all the
software and pack it up in a tarball. When starting the actual
bootstrapping process, debootstrap can then be pointed at that
tarball and use it instead of downloading anything from the internet.
If you plan on running the bootstrapper multiple times, this option
can save you a lot of bandwidth and time. This option just specifies
whether it should create a new tarball or not. It will search for and
use an available tarball if it already exists, regardless of this
setting.
optional
Valid values: true,false
Default: false

mirror: The mirror debootstrap should download software from.
It is advisable to specify a mirror close to your location (or the
location of the host you are bootstrapping on), to decrease latency
and improve bandwidth. If not specified, the configured aptitude
mirror URL is used.
optional

include_packages: Extra packages to be installed during
bootstrap. Accepts a list of package names.
optional

variant: Debian variant to install. The only supported value
is minbase and should only be used in conjunction with the
Docker provider. Not specifying this option will result in a normal
Debian variant being bootstrapped.

The packages section allows you to install custom packages from a
variety of sources.

install: A list of strings that specify which packages should
be installed. Valid values: Package names optionally followed by a
/target or paths to local .deb files.
Note that packages are installed in the order they are listed.
The installer invocations are bundled by package type (remote or local),
meaning if you install two local packages, then two remote packages
and then another local package, there will be two calls to dpkg-i...
and a single call to apt-getinstall....

install_standard: Defines if the packages of the
"StandardSystemUtilities" option of the Debian installer,
provided by tasksel, should be
installed or not. The problem is that with just debootstrap, the
system ends up with very basic commands. This is not a problem for a
machine that will not be used interactively, but otherwise it is nice
to have at hand tools like bash-completion, less, locate,
etc.
optional
Valid values: true, false
Default: false

sources: A map of additional sources that should be added to
the aptitude sources list. The key becomes the filename in
/etc/apt/sources.list.d/ (with .list appended to it), except
for main, which designates /etc/apt/sources.list.
The value is an array with each entry being a line.
Note: To use HTTPS-based repos, you need to add “apt-transport-https” and “ca-certificates” to include_packages (issue #476).
optional

components: A list of components that should be added to the
default apt sources. For example contrib or non-freeoptional
Default: ['main']

trusted-keys: List of paths (relative to the manifest) to .gpg keyrings
that should be added to the aptitude keyring of trusted signatures for
repositories.
optional

apt.conf.d: A map of apt.conf(5) configuration snippets.
The key become the filename in /etc/apt/apt.conf.d, except
main which designates /etc/apt/apt.conf.
The value is a string in the apt.conf(5) syntax.
optional

preferences: Allows you to pin packages through apt
preferences. The setting
is an object where the key is the preference filename in
/etc/apt/preferences.d/. The key main is special and refers
to the file /etc/apt/preferences, which will be overwritten if
specified.
optional
The values are objects with three keys:

bootstrap-vz allows a wide range of options for configuring the disk
layout of the system. It can create unpartitioned as well as partitioned
volumes using either the gpt or msdos scheme. At most, there are only
three partitions with predefined roles configurable though. They are
boot, root and swap.

partitions: A map of the partitions that should be created on
the volume.

type: The partitioning scheme to use. When using none,
only root can be specified as a partition.
Valid values: none, gpt, msdosrequired

root: Configuration of the root partition. required

size: The size of the partition. Valid values: Any
datasize specification up to TB (e.g. 5KiB, 1MB, 6TB).
required

mode: Set the mode bits of the mount point, e.g. ‘1777’ for /tmp

filesystem: The filesystem of the partition. When choosing
xfs, the xfsprogs package will need to be installed.
Valid values: ext2, ext3, ext4, xfsrequired

format_command: Command to format the partition with. This
optional setting overrides the command bootstrap-vz would normally
use to format the partition. The command is specified as a string
array where each option/argument is an item in that array (much
like the commands plugin).
optional The following variables are available:

{fs}: The filesystem of the partition.

{device_path}: The device path of the partition.

{size}: The size of the partition.

{mount_opts}: Options to mount the partition with. This optional
setting overwrites the default option list bootstrap-vz would
normally use to mount the partiton (defaults). The List is specified
as a string array where each option/argument is an item in that array.
optional Here some examples:

nodev

nosuid

noexec

journal_ioprio=3

The default command used by bootstrap-vz is
['mkfs.{fs}','{device_path}'].

boot: Configuration of the boot partition. All settings equal
those of the root partition.
optional

swap: Configuration of the swap partition. Since the swap
partition has its own filesystem you can only specify the size for
this partition.
optional

additional_path: Configuration of additional partitions. (e.g. /var/tmp)
All settings equal those of the root partition.